Hi,

I have a Minolta Autometer IVF. Up until now I've only used it for ambient
light metering, for which it has been fine.
Now, at my photography club, we are starting a studio group, and here's
where the funny situation starts....
Two other guys are loaning their studio flashes.
My flash meter (IVF) seem to give different readings to their flash meters,
by about 3 stops high (they read f/11 and my meter says f/32, in incident
light mode.)
Ok, so my meter is faulty, it would seem.
But, at home I have a couple of smaller studio-style units (bit small for
full body work, but ok for portraits and still-life) and with these the
meter seems to read correctly. I've compared it with my Spotmeter F, firing
the flash at a large sheet of card.

So, any thoughts on what is going on here?

I've also roughly checked the meter by firing the flash at a large grey card
and working out the exposure from the guide number. Allowing for an
optimistic guide number, it is in the right 'ball park'. Also, I've dug out
an old portable flash and tested the meter with that, also ok.

Now, the last point, which may be the telling one. All the above was done
using reflected light  metering.
When I compare readings in reflected mode with those in incident mode, the
incident ones are a lot higher (3-ish stops). Why is this?
I aim the flash at a large grey card and measure the reflected light from
about a metre away, then I put on the incident dome and measure again with
the meter against the card, facing the flash. Should these not read the
same, roughly?

I can get the meter checked out and fixed by Minolta, but it's not cheap and
I get the feeling that something odd is going on here.  Probably mejust not
understanding, bu all advice gratefully received.

John